Salmon by-products are excellent source of polyunsaturated fatty acids, especially omega-3 and omega-6. A series of small studies on the production of omega-3 concentrates from salmon by-products (head, gut and frame) was carried out. Because raw material must be of highest quality for the production of nutraceuticals (i.e. omega-3 capsules), spoilage rates and fatty acid composition changes were examined by applying different handling and pretreatment procedures. Further, different enzymatic methods for concentrating omega-3 fatty acids from oil were compared.
Overall, based on our observations it can be concluded, that the oil extraction method developed maximizes recovery of oil using a gentle enzymatic method. The impacts of handling and pretreatment of salmon waste were investigated and will gives important direction when evaluating practical processes for waste utilization. Also, significant conversion of oil into omega-3 concentrates was achieved using an enzymatic process. Here, temperature was identified as the most influential parameter and it was concluded that, while promising, additional tests are necessary to optimize the method. This is a pioneer study in case of fatty acids extraction and concentration from fish by-products, which can be used as a reference for future studies and will also be useful for designing and augmentation of experiments in this area of study. Last but not least, this study facilitated the further development of the scientific staff at the Bioprocessing unit of the Centre of Aquaculture and Seafood Development, allowing future support of the industry and academic groups in the areas of by-products utilization, edible oil analysis and edible oil refining and polishing.
The knowledge and experience gained by the Bioprocessing team and the fine-tuned analytical methods, especially GC (Gas Chromatography) will be highly valuable for academic and industry use in future projects.